During pregnancy, adverse events in the mother such as infection and pregnancy complications that result in immune responses have been linked with neuropsychiatric disorders in the offspring. In addition, prenatal stressors have also been shown to drive immune responses during pregnancy with resulting adverse consequences for offspring. Proinflammatory cytokines, or an imbalance between pro-and anti-inflammatory cytokines, are suggested as one of the underlying mechanisms that explain the association between these immune response events and children?s risk of neuropsychiatric disorders. In order to investigate the association between fetal exposure to biomarkers of maternal immune activity throughout gestation and children?s neurocognitive development up to age 7 ages, we propose to use samples from the Collaborative Perinatal Project (CPP). The CPP was conducted between 1959 and 1966 and designed to examine the relationships between perinatal events and neurological defects of the offspring in a total of 55,908 women across 12 hospitals. Offspring were followed through age 7, with approximately 70% retention for the duration of the study. Maternal serum was extracted from blood collected serially during pregnancy from the date of study registration through delivery and stored in the National Institutes of Health repositories at minus 20 degrees Celsius. The Division of Intramural Population Health Research (DIPHR) has identified approximately 3,700 (3,697) serum specimens in the NICHD-DIPHR repository from CPP participations, from which assays of immune activity will be conducted. Measurement of immunological markers from these specimens will allow investigation of the association between fetal exposure of biomarkers of maternal immune activity and the child?s neurocognitive development, and allow for investigation of these associations within specific pregnancy trimesters. The task order is to use Q-PlexTM Human Cytokine HS screen (for 15 cytokines) and individual assays to detect IL-8, hsCRP, BDNF, and IL-1R1 antagonist from 2697 CPP serum samples.